I had a meeting with Kadokawa, one of the biggest publishing company group in Japan. Guys working on EPUB in Japan had setup a meeting with them and kindly invited me, so I'm writing this to share what I heard at the meeting with whom interested in digital publishing situations in Japan.
About a month ago, the EBPAJ (The Electronic Book Publishers Association of Japan)[1] made an announcement[2] that they have started a project to test interoperability of EPUB readers. As EPUB3 became REC last October, and readers started appearing in the market, they soon realized that interoperability is one of the issues they need to resolve. The EBPAJ is primarily focused on magazines, and Kadokawa is one of the central member of the activity within the EBPAJ.
They believe in future of EPUB and W3C technologies so much that they want to solve problems they can, and this project is one of such efforts. They're planning to do the followings in this project:
1. Listen to the member publishers to create a list of features and test cases they would care.
2. Create a test suite and ask which features vendors support. The group will also run tests for major readers and browsers by themselves.
3. Publish the result so that content holders can decide which platforms to support. They expect the result also helps creating in-house rules to author interoperable HTML/CSS/EPUB for readers/browsers they want to support. They target to publish the result on March 2012.
They also mentioned that the glyph orientation in vertical text flow is one of the issues they are looking into, which is one of the hottest topic in writing-modes[3] and UTR#50[4]. It used to happen in the past that digital publishing platforms rendering different glyph orientation by OS/fonts, so they were not surprised much, but they recognized that EPUB has the issue and that they need to investigate further. They're welcoming our efforts to define orientations in the spec, although, no promise on dates is one of the biggest concern. How they would test it hasn't finalized yet, I'll keep in touch with them.
It looked to me that they were a bit surprised that many symbol and punctuation glyphs used in their contents appear in sideways in today's implementations, more than in other existing digital publishing platforms. But they're professional content holders that, once spec was finalized and implemented (or they have figured out behavior if spec didn't meet their timeframe,) they could create internal rules or system to wrap every symbol and punctuation character in <span>s and set the text-orientation property[5] on them. They said they can live with any rules as long as the rules are clear, there's a workaround (i.e., span + text-orientation property,) and it won't change, but it still holds true that the less <span>s they need to use, the better.
[1] http://www.ebpaj.jp/ (Japanese)
[2] http://www.ebpaj.jp/images/epub_20111216.pdf (Japanese)
[3] http://dev.w3.org/csswg/css3-writing-modes/
[4] http://www.unicode.org/reports/tr50/
[5] http://dev.w3.org/csswg/css3-writing-modes/#text-orientation
Regards,
Koji